1. Field of the Invention
This invention relates to apparatus and a method for handling containers moving along a linear conveyor line so that the containers may be diverted from the conveyor line to an off-line station adjacent to the conveyor line. The handling device is conveniently mounted to move into and out of position to permit the containers to continue to move on-line or to be diverted off-line and then returned on-line.
2. Description of the Prior Art
In the manufacturing of bottles, cans, or other types of containers, it is common to transport the containers from one manufacturing position to another by means of conveyors which move horizontally in a straight line between the positions. During the manufacturing process and during the filling of the containers, it is often necessary or desirable to divert the containers from the linear conveyor to an off-line station for inspection of the container or its contents. After the container passes through the off-line station, it is desirable to return it to the linear conveyor downstream from the off-line station so that the container may continue along the conveyor to the next manufacturing or filling position.
In the manufacturing of bottles, for example, it is often desirable to photoelectrically scan the bottles for defects at an off-line station adjacent to the conveyor upon which the bottles are moving. Many prior attempts have been made to satisfactorily provide an apparatus that removes a container from a moving linear conveyor, passes it through an off-line station, and returns it to the moving linear conveyor at a point downstream from the off-line station.
An example of such an earlier device is shown in U.S. Pat. No. 3,150,758 wherein a starwheel or turret member is utilized to remove bottles from a conveyor. The starwheel is periodically rotated by means of a Geneva-type drive assembly. Flexible retainer bands are provided around the starwheel to retain bottles within the recesses in the starwheel as the starwheel rotates.
Other devices for moving containers through the use of starwheels or indented turrets are shown in U.S. Pat. No. 1,132,172; U.S. Pat. No. 1,828,324; U.S. Pat. No. 4,230,219; U.S. Pat. No. 1,594,465; U.S. Pat. No. 1,825,751; U.S. Pat. No. 1,844,869; and U.S. Pat. No. 3,717,236.
The use of a starwheel or an indented turret presents some difficulties in synchronizing moving bottles or other containers into the correct position to be captured by the starwheel pockets from a moving linear conveyor. The rotation of the starwheel must be synchronized with the linear speed of the bottles or containers on the conveyor and with the spacing between the bottles in order to precisely receive the bottles within the recesses of the starwheel. This high degree of precision is difficult to maintain. Additional problems are encountered with a starwheel to accommodate a change in container size or shape. For a job change of this type to be executed extensive parts changes are required resulting in substantial downtime. For each container size, a corresponding starwheel must be assembled in the conveyor line.
There is a need for an off-line container handling device capable of receiving containers moving in a linear path without regard to the speed or spacing between containers, additional mechanical parts to match the size of the bottles, and interruption in the conveyance of the containers.